Mix first 3 ingredients in small bowl. Stir chocolate and butter in top of double boiler set over simmering water until melted and smooth. Turn off heat. Let chocolate stand over water.

Using electric mixer, beat eggs and sugar in large bowl until mixture thickens and falls in soft ribbon when beaters are lifted, about 5 minutes. Beat in vanilla. Stir in flour mixture in 2 additions, blending well after each. Gradually add warm chocolate to egg mixture, beating until just combined. Stir in walnuts.

Pour batter into prepared pan. Bake brownies in preheated oven until top is set and tester inserted into center comes out with moist crumbs attached, about 35 minutes. Cool completely in pan on rack.

For Ganache: Whisk all ingredients in small saucepan over medium-low heat until melted and smooth. Pour evenly over brownies in pan.

Reviews

Reviewer: JenRating:Review:I thought that they were good but nothing special. I did not use the nuts maybe that is what they needed.

Reviewer: SanazRating:

Reviewer: Jessica PierceRating:Review:These other reviewers are crazy. This is among the best brownie recipes I've ever made. The ganache was spot-on perfect. Texture of brownie was much denser, fudgier than I'd have ever guessed from the thin batter. Super rich, super easy & definitely going into rotation at my house.